An 18-year-old female student was shot in the arm. The same bullet then entered a 17-year-old male student’s shoulder. Both victims were taken to Albert Einstein Medical Center.

Responding officers immediately secured the school and discovered that the suspects involved had fled from the building.

One of suspects surrendered to police Saturday afternoon and has been charged with aggravated assault and related offenses.

A second student turned himself in to authorities on Friday evening. He has since been released and has not been charged. A 15-year-old student who was taken into custody immediately following the incident was completely exonerated.

“I mean it was just chaos. It was real chaos,” a teacher said.

“My friend got shot,” a student said. “I’m making sure he’s alright.”

He spotted a trail of blood on the floor, worried about his friend’s condition.

“You don’t expect stuff like this to really happen,” he said. “It’s crazy.”

Fortunately, neither of the students’ injuries was considered life-threatening. The female victim was discharged from the hospital. The male victim remained hospitalized in stable condition.

After police determined those involved in the shooting had left the school, worried parents began arriving (See Related Story).

“She was just crying and hysterical, just telling me they just had a shootout and two students got shot,” parent Dawn Humbert said.

As the search for the weapon moved into the evening, with federal agents joining Philadelphia investigators, sources tell CBS 3 it appears the shooting may well have been an accident. A student carrying or perhaps showing off a gun to others when it went off.

(Reporter:) “Do you feel like a major tragedy was averted today?”

“Any time someone doesn’t die it’s a major tragedy averted, but it’s still a tragedy. And, you know, it just shouldn’t happen,” Philadelphia Police Commissioner Charles Ramsey said.

The shooting here is the second incident involving a weapon at a charter school in the last few days. Earlier in the week, a 17-year-old arrested at a West Philadelphia charter school with a fully loaded .45 semi-automatic in his book bag (See Related Story).